Separable attachment-plug.



R. B. BENJAMIN. SEPARABLE ATTACHMENT PLUG. APPLICATION FILED NOV-21,1908.

1 15%,963. PatentedSept. 28, 1915;

2 SHEETS-SHEET I.

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R. B. BENJAMIN.

SEPAHABLE ATTACHMENT PLUG. APPLICATION EIVLED NOV-21. 190a.

2 SHEETS-SHEET 2.

' Wrrzeya PatehtedSept. 28, 1915.

- Be it known that I, REUBEN 'a citizen of the United States, reslding at pnirnn s aarns Par onrrcni.

REUBEN- B. BENJAMIN, OF CHICAGO, ILLINOIS, ASSIGNOR TO BENJAMIN ELECTRIC MANUFACTURING COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

SEPARABLE ATTAGHMIEINT-PLUG.

Specification of Letters Patent.

Patented Sept. 28,1915.

Application filed November 21, 1908. Serial No. 463,764.

To all whom it may concern:

Chicago, in the county of Cook and State of Illinois, have invented new and useful Improvements in Separable Attachment-Plugs, of which'the following is a full, clear, concise, and exact description, reference being had to the accompanying drawing, forming a part of this specification.

This invention relates to separable at tachment plugs, which, as is well known, consist of two members, one of which is provided with contacts for cooperation with the contacts of the socket, and the other of which carries binding terminals, these members being detachably connected together in such manner that, when assembled, electrical connection is made between the contacts on the one member and the binding terminals on the other member. Such plugs are of articular use in cases wherein it is desir. 1e for an electric translating device, such as afan, motor or the like, to be more speedily connected to, and disconnected from, a socket than is possible when using a one-piece plug.

Separable lugs, as hitherto constructed, have been su ject to the disadvantage that considerable force was necessary to detach B. BENJAMIN,

one portion, from the other. This was owing to the'fact that, in most cases, the plug members telescoped together, a contact piece on one member engaging between spring contacts on the other; so that the frictional resistance, and'the resistance to bending, of the spring contacts had to be overcome before one member could be separated from the other. When this frictional resistance and resistance to bending were provision of a simple and reliable separable plug of economical construction and neat appearance.

For a full understanding of my invention, reference is to be had to the accompanying description and drawings, in which I have shown a form of device embodying my invention.

Figure l is an elevation of the device with the separable members interconnected; Fig. 2 shows these parts separated from each other; Fig. 3 shows the body, or binding terminal carrying member, separated from the other member and revolved to present the side opposite that seen in Fig. 2; Fig. 4 is a plan view of this body member; Fig. 5 is an inverted plan view of the other member; Fig. 6 is a vertical section on the line 6-6 of Fig. 1; and Fig. 7 is a reduced fragmentary view of one of the details of the device.

Like characters of reference refer to like parts throughout the specification and drawings.

In the form of my invention illustrated herein, the part which carries the socketterminal-engaging contacts consists of a shell 10, adapted for insertion into the socket, and a body 11, which carries bindin terminals to which are secured the flexible conductors leading to the fan or other electriccurrent consuming device, the body 11 being removably inserted in the shell 10, as will be hereinafter fully described.

The shell 10 comprises a metallic sleeve 12 having screw threads formed thereon adjacent its upper end for engaging the internal threads of an ordinary Edison socket. This sleeve 12 is formed with an inwardly turned upper end flange "14 and an outwardly turned lower end flange 13, and with an inwardly extending circumferential bead 15 and an outwardly extending 'circumferential bead 16 intermediate its ends, the beads 15 and 16 being preferably lo- .cated adjacent each other and immediately below the termination of the screw threaded portion of the sleeve. Surrounding the lower portion of the sleeve 12, and held between the flange 14: and the head 16, is a ring 17, formed of insulating material. such as hard rubber or the like, and having an outwardly extending flange 18 which is preferably knurled at its periphery to provide a firm hold for the fingers of the user. A cup-shaped block 19 of insulating material is inserted in the upper end of the sleeve 12 and has formed "thereon an outwardly extending flange 20 which abuts against the of the sleeve 12.

The block 19 is formed .with a central aperture 22 in which is secured the center flange 14. The block 19 isheld in place by an insulating ring 21 located between the lower side of its flange 2Q and the beadf contact of the plug. The center contact consists of a tubular member 23 which passes through the aperture 22 and'is bent outward to form a flange 24 outside the 2 block '19. The tubular member 23 is also formedwith a flange 25, within the block 19. One end of a resilient inner contact 26,

which preferably consists of a substantially U-shaped plate of spring brass, surrounds the 'tubularmember 23 and is clamped between the flange 25 and the'inner side of the block 19.

The sleeve 12 is formed with inwardly extending bayonet projections-27 adjacent its lower edge, said projections tapering slightly upward to one side for a purpose to be hereinafter described. A small. ex-. crescence' 28 is formed adjacent the thicker end of one of the projections 27 By building up the shell as above described, instead of, as is usual in earlier forms of separable plugs, constructing .it of a single hollow porcelain part having a sleeve. contact secured thereon, a larger I space is provided within the shell, thus enabling the bodylto be made of larger proportions than has hitherto beenconsidered possible. This is an important advantage I of the plug since it. enables the insulating properties of the body to be increased, and

a portion 30 atits upper end. The base29 is formed with a side recess 31 extending from one end thereof to the other for conr taining the end of the conductor 32.

' contact resting upon the'upper' end of the the binding terminals to be so located on the body as to be readily accessible.

The body 11 comprises an insulating base 29 of less diameter than the internal diameter of the sleeve 12 and having a tapered A second recess" 33 is also formedat the upper end of' the plug, a passage 34,..which opens at one end into the recess 33, extending through the plug and having an enlarged portion 35 at the end thereof adjacent the lower face of the: plug.

Located in therecess 33 is the, shank 36 of the end contact 37 of the body, the. end

'1 base 29, and having its shank bent d0wnwardly and outwardly to snugly'fit in the recess 33. The shank" 36 has an aperture formed therein, which, when the end conrecessesl47 may be possible.

tact is in position, registers with the passage 34, and a hollow metallic rivet 38 is passed through this aperture and the passage 34 and flanged over at one end against the shank 36 and at the other end against the shoulder formed by the enlargement 35 of the passage 34. This rivet securely holds the shank 36 in position in the recess 33.

secured .in the cup by bending portions of the upper edge of the latter over ledges I formed uponthe base. Secured,'by rivets, or otherwise, to the cup 41, and so located as to enter the recess 31, is a conductorplate 44 preferably so shaped that'suflicient room is" left between it and the inner face of the recess 31 to allow of the passage of the bared end of the conductor 32 therethrough, an upwardly bent lug 45 being formed on the conductor plate 44'for the purpose of precluding any chance of the conductor slip ping around the conductor plate to the outside thereof. A binding terminal 46 is screwed into the conductor plate 44 and clamps the end of the conductor 32. The

cup 41 is bent inwardly 1 at one or more points at its periphery to form recesses 47, such recesses being of the same number as the bayonet projections 27 on the sleeve 12 of the shell-10, and so located as to register with the projections 27 when the body 10' is inserted in the shell-10. Flat places 48 are formed upon the base 29 in order that the bending in of the cup 41 to form the Screwed into the collar 42 is the screw-threaded neck 49 of the handle .50, which is constructed of- 1 hard rubber or other insulating material, and is formed with an upturned flange or skirt 51 which incloses the collar 42. The conductors 32 and 40 pass through the neck 49, which latter is of such length that, when screwed firmly into the collar 42, it clamps :the conductors against the lower end of the base 29 and precludes any chance of their detachment from the binding terminals by.

an accidental jerk or the like.

In using the plug, the shell .10 is screwed into the socket until the flange 24 of its center contact. makes connection with the center contact of the socket. When thus connected,-the shell 10 cooperates with the Edison socket to form a socket of a different internal configuration, and, of the socket so formed, 26 is one contact and the lower portion of the sleeve 12 the other. The body 11 then becomesa plug, the end contact 37 and cup 41, to which the conductors 40 and 32 are respectively connected, engagingthe inner contact 26 and the inner face of the sleeve 12. The body 11 and shell 10 are preferably so proportioned that, when the body is inserted in the shell, (the projections 27 of the shell entering the recesses 47 of the body), the end contact 37 will engage the inner contact 26 of the shell slightly before the projections 27 reach the lower end of the recesses 47, so that it is necessary to, compress the inner contact 26, 'which is-ma de resilient to that end, before the projections can pass beyond the lower end of the cup 41. When the body 11 has been thus forced against the inner contact 26 until the projections 27 have passed through the recesses 47 and beyond the lower end of the cup,- it is-turned relatively to the shell so that the projections 27 engage beneath the shoulder 41 of the cupv 41 and are held in such engagement by reason of the resilience of the inner contact 26. The upward slope of the projections 27 causes the end contact 37 to be forced more firmly against the inner contact 26 when the body is rotated. The stop 28 limits the possiblle turning movement of the bodyin the she In order to connect the body to the shell, all that is necessary is that the body be firmly pushed into place and given a slight twist, while a slight twist in the opposite direction is suficient to detach it.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent, is v 1. In a separable plug; a body comprising a base, a cup-shaped contact member surrounding the lower end of said base and carrying a binding terminal and an end contact secured to said base and carrying a sec- 0nd binding terminal; and a shell for receiving said body, said shell comprising a con tact sleeve for engaging said cup-shaped contact and an inner contact for engaging said end contact. I

2. In a separable plug; a shell comprising a conductor sleeve screw threaded at its upper end, an insulating block within said sleeve and projecting beyond the end thereof, an outer end contact carried by said block, an inner contact carried by said block and electrically connected with the outer end contact, an insulating ring carried within the upper end of said sleeve and an-insulating ring carried by the lower end of said sleeve outside the same; and a body insertible into said shell and having contacts for 3. An attachment plug comprising a screw shell having at its forward end an insulating head carrying a contact plate and a contact spring connected therewith, an inner shell, an insulating block within said shell carrying a contact plate adapted to engage the contact spring, means for detachably securing the shells together and electrical connections.

4. A screw shell having at its forward end an insulating head, a contact plate on the outer side of said head, a contact spring on the inner side thereof and an electrical con nection between said contact plate and contact spring.

5. An attachment plug comprising an outer member having at its forward end an insulating head carryinga contact plate and a contact spring connected therewith, an inner member comprising an inner shell and adapted to engage the contact spring, means for detachably connecting said members tofrom onebinding screw to the shells and electrical connections from the other binding icregv to the contact plate on the insulating ea a 7. An attachment plug-comprising a screw shell having at its forward end an insulating head carrying a contact plate, an inner shell detachably engaging the screw shell, an insulati'ngblock in the inner shell, binding screws carried by said block and electrical connections from one binding screw to the screwshell and from the other binding screw to said contact plate.

8. An attachment plug comprising a screw shell having at its forward end an insulating head carrying a contact plate, an inner shell detachably engaging the screw shell, an insulating block in the inner shell, binding screws carried by sald block, a contact plate connecting one binding screw with the inner shell and electrical connections from the other binding screw to the contact i an insulating block carrying a contact plate screw shell and an insulating head carrying scribed my nanie in the presence'oftwo wita contact plate and contact spring, of an nesses. inner member comprising an inner shell and an insulating block carrying a contact plate 5 adapted to engage the contact spring and Witnesses: r

electrical connections. I g CHARLES G; COPE,

In Witness whereof, I have hereunto sub- CHARLES L. Horxms.

REUBEN B. BENJAMIN; 

